JP5245187B2 - Polyamideimide, liquid crystal aligning agent varnish, and liquid crystal display element - Google Patents

Abstract

PURPOSE: To provide a liquid crystal aligner for obtaining a liquid crystal display element with appropriate pre-tilt angle, excellent in overall balance of liquid crystal alignability, electric characteristics (consumed current value, voltage holding capacity, remained charge, sticking) or the like. CONSTITUTION: This polyamideimide comprises only one structural unit expressed by formula (1-1), or two or more kinds among three structural units expressed by formulae (1-1), (1-2) and (1-3), respectively, wherein at least one organic residue derived from carboxylic acids and organic residues derived from diamino compounds is the organic residue having >=3C side chain and >=30 mol% of whole amide bondages in the polymer is the amide bondage in which monovalent organic group is bonded to N. In the formulae, T¬1 to T¬3 each denotes an organic group derived from carboxylic acids, D¬1 to D¬3 each denotes an organic group derived from diamino compounds, and R¬1 to R¬3 each denotes hydrogen or monovalent organic group.

Description

  The present invention relates to a novel polyamide-imide having excellent liquid crystal orientation, electrical properties and reliability used in the field of electronic materials.

  Currently, display devices using nematic liquid crystal are mainly used as liquid crystal display devices. TN liquid crystal display devices in which liquid crystal is twisted by 90 degrees, STN liquid crystal display devices in which twist is usually 180 degrees or more, and so-called TFTs using thin film transistors are used. Type liquid crystal display elements are known. Furthermore, recently, various types of display such as a lateral electric field type IPS liquid crystal display element with improved viewing angle characteristics, a VA liquid crystal display element using a vertical alignment state, or an OCB type liquid crystal display element using a bend alignment state are used. Devices have been put into practical use or are being studied. The progress of liquid crystal display elements is actively made not only by the progress of these methods but also by improvements in peripheral materials for improving the characteristics of liquid crystal display elements. Further, the liquid crystal aligning agent is one of the important elements related to the display quality of the liquid crystal display element, but the role of the liquid crystal aligning agent is increasing as the quality of the display element is required.

  Currently, the liquid crystal aligning agent mainly used is a polyimide system such as a polyamic acid and a soluble polyimide which are used by imidizing a polyamic acid. Various liquid crystal alignment agents other than polyimide-based alignment agents have been studied, but these have insufficient heat resistance, chemical resistance (liquid crystal resistance), coating properties, liquid crystal alignment properties, electrical characteristics, display characteristics, etc. It is believed that there is. Among polyimide-based alignment agents, polyamic acid is highly soluble in solvents and has good substrate coatability, but requires a baking step of imidization by heating when forming an alignment film, and the properties deteriorate at low temperature baking. There's a problem. On the other hand, soluble polyimides have a problem that solubility in solvents is relatively poor even though they are soluble, and that printability is inferior because only a limited solvent can be used.

  In addition to polyimide-based alignment agents, high molecular compounds such as so-called N-substituted polyamides in which hydrogen atoms of polyamides or polyamide amide bonds (CONH) are substituted with other groups have been studied. Polyamide has good liquid crystal orientation and the like, but has some difficulty in solubility and printability, and has a problem with electrical characteristics. Conversely, N-substituted polyamides have good solubility, printability, and electrical properties, but may be slightly inferior in liquid crystal alignment. There are also liquid crystal alignment agents that use a polymer compound blended with multiple polymer compounds or block copolymerization, but in terms of electrical characteristics such as current consumption, residual charge, voltage holding ratio, image sticking, or liquid crystal alignment. The current situation is difficult. The requirements for liquid crystal aligning agents are difficult to put into practical use even if only certain properties are excellent, and it is necessary to have a comprehensively balanced characteristic.

  As the field of use of liquid crystal display elements expands, the characteristics required for liquid crystal display elements are becoming higher performance. Among these requirements are the requirements for the orientation of the liquid crystal typified by the pretilt angle of the liquid crystal, the requirements for the electrical characteristics of the liquid crystal display element such as the current consumption value, the voltage holding ratio, the residual charge, etc. There are demands for reliability in long-term use of characteristics, demands for display quality such as afterimage phenomenon of liquid crystal display elements, display unevenness, and the like.

  Among these characteristics, the required value of the pretilt angle of the liquid crystal differs depending on the driving method of the liquid crystal display element. For example, a pre-tilt angle of about 1 to 6 degrees is required for a TN type liquid crystal display element or a TFT type liquid crystal display element in which the liquid crystal is twisted by 90 degrees, and about 3 to 8 degrees is required for an STN type liquid crystal display element having a large twist angle. . However, these required pretilt angle values vary somewhat depending on the application. Recently, STN type liquid crystal display elements may require 2 to 3 degrees or more than 8 degrees. On the other hand, in the IPS liquid crystal display element, since the liquid crystal moves in the horizontal direction with respect to the substrate, it is not necessary to increase the pretilt angle, and the pretilt angle may be about 1 to 3 degrees. Conversely, a VA liquid crystal display element requires a large pretilt angle near 90 degrees, and an OCB liquid crystal display element also requires a large pretilt angle of 5 to 20 degrees to stabilize the bend alignment state. The

  Further, not only the pretilt angle but also characteristics relating to the alignment of the liquid crystal such as alignment uniformity, alignment stability or anchoring energy at the liquid crystal-alignment film interface are important because they greatly affect the performance of the liquid crystal display element. Furthermore, the process margin of these characteristics in the manufacturing process of the liquid crystal display element is also important, and the pretilt angle and the orientation change depending on the drying conditions of the solvent after applying the aligning agent or the annealing treatment conditions after injecting the liquid crystal. It will be a big problem.

  In a STN type liquid crystal display element, particularly a low voltage type display element used in the field of portable devices, a demand for current consumption is important because the driving voltage is low. That is, when the current consumption of the liquid crystal display element is increased, the voltage applied to the liquid crystal is relatively decreased, so that the rise of the liquid crystal is insufficient and the contrast is decreased. Further, in a low voltage type liquid crystal display element, a change (reliability) of a consumption current value that occurs during long-term use of the liquid crystal display element is also important. In the STN type display element, display is turned on and off with a slight potential difference. Therefore, if the current consumption value of the element changes, the voltage applied to the liquid crystal also changes and normal driving cannot be performed. In extreme cases, even a phenomenon in which an image of the liquid crystal display element is not displayed at all occurs due to long-time driving.

  On the other hand, in the TFT type liquid crystal display element, the requirements for the voltage holding ratio and the residual charge are particularly important. If the voltage holding ratio is low, the voltage applied to the liquid crystal during the frame period is lowered, causing a problem that the contrast is lowered. If the residual charge is large, even if the voltage is turned off after the voltage is applied, the charge remains, and an image to be erased remains as an afterimage. In the TFT type liquid crystal display element, this afterimage phenomenon is one of very important problems.

  Furthermore, as liquid crystal having a large dielectric anisotropy is used in recent years as the driving voltage is lowered, display unevenness (brightness unevenness) generated in the surface of the display has become a problem. Yes. In particular, when water washing for removing shavings generated when the alignment film is rubbed is performed, a phenomenon that the marks after the water washing remain as display unevenness may occur, which is a serious problem.

Problems to be solved by the invention

  The present invention has a particularly suitable pre-tilt angle among the characteristics required for the above-mentioned liquid crystal display element, and has comprehensive characteristics such as liquid crystal orientation and electrical characteristics (current consumption value, voltage holding ratio, residual charge, burn-in). It is another object of the present invention to provide a liquid crystal aligning agent for obtaining a liquid crystal display element having an excellent balance.

Means for solving the problem

（式中、Ｔ^１〜Ｔ^３はカルボン酸類由来の有機残基であり、Ｄ^１〜Ｄ^３はジアミノ化合物由来の有機残基であり、Ｒ^１〜Ｒ^３はそれぞれ独立して水素または１価の有機基である。この１価の有機基は、炭素数１〜２０の直鎖もしくは分岐のアルキル、炭素数１〜８の直鎖もしくは分岐のヒドロキシアルキル、炭素数２〜２０の直鎖もしくは分岐のアルコキシアルキル、炭素数２〜１５の不飽和脂肪族基、脂環式基を有する基、芳香族系炭化水素基、Ｏ含有複素環系の基、ステロイド骨格を有する基、カルボニル基を有する基、オルガノシリル基、およびオルガノシリル基含有基からなる群から選択される１種以上の基であり、前記のアルキル中の任意のＨはＦで置換されてもよく、前記の芳香族系の炭化水素基においては、芳香環とアルキルまたはアルキレンとがＯを介して結合してもよく、芳香環の置換基であるアルキルのＨはＦで置換されてもよく、また芳香環の１個のＨがＣＮで置換されてもよい。）
（２）式（２）〜式（５）のそれぞれで表される基の群から選ばれるジアミノ化合物由来の有機残基が少なくとも１種含まれていることを特徴とする、前記（１）項に記載のポリアミドイミド。

（式中、Ｒ^４はＨまたは炭素数１〜１２のアルキルであり、環Ａは１，４−フェニレンまたは１，４−シクロヘキシレンであり、Ｚ^１およびＺ^２はそれぞれ独立して単結合、ＣＨ_２、ＣＨ_２ＣＨ_２またはＯであり、ｒは０〜３、ｓは０〜５、ｔ１は０〜３、ｔ２は０〜３のそれぞれ整数であるが、ｔ１が２〜３である時の複数のＺ^１は互いに同じであっても異なっていてもよいし、またｔ２が２〜３である時の複数のＺ^２も互いに同じであっても異なっていてもよい。また、１，４−フェニレンまたは１，４−シクロヘキシレンの任意のＨは炭素数１〜４のアルキルで置換されていてもよい。）

（式中、Ｘ^１およびＸ^２はそれぞれ独立して単結合、Ｏ、ＣＯＯ、ＯＣＯ、ＮＨ、ＣＯＮＨまたは炭素数１〜１２のアルキレンであり、Ｇ^１およびＧ^２はそれぞれ独立して単結合、または芳香族環および脂環式環から選ばれる１〜３個の環を含む二値の基であり、Ｒ^５はＨ、Ｆ、ＣＮ、ＯＨまたは炭素数１〜１２のアルキル、フルオロアルキルもしくはアルコキシであり、ベンゼン環に対する置換基の結合位置および２個の遊離基の位置は任意の位置である。但し、Ｇ^２が単結合でありＸ^２が単結合でもなくアルキレンでもない場合は、Ｒ^５はＨまたはアルキルであり、またＧ^１およびＧ^２が共に単結合である場合は、Ｘ^１、Ｘ^２およびＲ^５の合計の炭素数が３以上である。）

（式中、Ｘ^３およびＸ^４はそれぞれ独立して単結合、ＣＨ_２、ＣＨ_２ＣＨ_２またはＯであり、Ｒ^６およびＲ^７はそれぞれ独立してＨ、炭素数１〜１２のアルキル、または炭素数１〜１２のパ−フルオロアルキルであるが、Ｒ^６およびＲ^７の少なくとも一方は炭素数３以上のアルキルまたはパ−フルオロアルキルであり、ｕ１およびｕ２はそれぞれ独立して０〜３の整数であるが、ｕ１が２〜３である時の複数のＸ^３は互いに同じであっても異なっていてもよいし、ｕ２が２〜３である時の複数のＸ^４も互いに同じであっても異なっていてもよい。また、１，４−フェニレンの任意のＨは炭素数１〜４のアルキルで置換されていてもよい。）

（式中、Ｒ^８はＨ、または炭素数１〜１２の直鎖もしくは分岐状のアルキルであり、このアルキル中の１個もしくは隣り合わない複数のＣＨ_２はＯで置換されていてもよく、Ｘ^５は単結合、または炭素数１〜５のアルキレンであり、このアルキレン中の１個もしくは隣り合わない複数のＣＨ_２はＯで置換されていてもよく、ｍは０〜３の整数であり、ｎは１〜５の整数である。また、ベンゼン環に対する置換基および遊離基の結合位置は任意の位置である。）
（３）Ｒ^１、Ｒ^２およびＲ^３がそれぞれ独立してＨまたは炭素数５以下の１価の有機基であって、Ｒ^１〜Ｒ^３の総量の５０モル％以上が該１価の有機基であることを特徴とする、前記（１）または（２）項に記載のポリアミドイミド。
（４）Ｒ^１、Ｒ^２およびＲ^３がそれぞれ独立してＨ、炭素数５以下のアルキルまたは炭素数５以下の酸素含有アルキルであって、Ｒ^１〜Ｒ^３の総量の７０モル％以上がこれらのアルキルおよび酸素含有アルキルから選ばれる１価の有機基であることを特徴とする、前記（１）または（２）項に記載のポリアミドイミド。
（５）前記（１）〜（４）項のいずれか１項に記載のポリアミドイミドを含有することを特徴とする液晶配向剤ワニス。
（６）前記（５）項に記載の液晶配向剤ワニスが用いられていることを特徴とする液晶表示素子。
上記の構成による本発明のポリアミドイミドは、配向膜、保護膜、絶縁膜等として使用でき、とりわけ、液晶表示素子用の配向膜を形成するための配向剤ワニスとして最適である。そして、本発明のポリアミドイミドは、ポリアミド酸、可溶性ポリイミド、ポリアミド等の他の高分子化合物と併用することにより、配向剤ワニス等の特性を更に向上させることができる。As a result of diligent research for solving the above-mentioned problems, the inventors of the present invention have achieved the intended purpose by using a liquid crystal alignment agent varnish used in a liquid crystal display element containing a polyamideimide having the following constitution. Found that can be achieved.
That is,
(1) It has only the structural unit represented by Formula (1-1) among the structural units represented by each of the following Formula (1-1), Formula (1-2), and Formula (1-3). Or a polyamideimide having two or more of these three types of structural units, wherein at least one of an organic residue derived from a carboxylic acid and an organic residue derived from a diamino compound is a side chain having 3 or more carbon atoms A polyamideimide, which is an organic residue having a group, and 30 mol% or more of all amide bonds in the polymer are amide bonds in which a monovalent organic group is bonded to N.

(Wherein T ^{1 to} T ³ are organic residues derived from carboxylic acids, D ^{1 to} D ³ are organic residues derived from a diamino compound, and R ^{1 to} R ³ are each independently hydrogen or monovalent. The monovalent organic group is a linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched hydroxyalkyl group having 1 to 8 carbon atoms, a linear chain group having 2 to 20 carbon atoms, or Branched alkoxyalkyl, C2-C15 unsaturated aliphatic group, group having alicyclic group, aromatic hydrocarbon group, O-containing heterocyclic group, group having steroid skeleton, carbonyl group One or more groups selected from the group consisting of a group, an organosilyl group, and an organosilyl group-containing group, and any H in the alkyl may be substituted with F, In hydrocarbon groups, aromatic rings and Kill or alkylene may be bonded through O, H in the aromatic ring substituent may be substituted with F, and one H of the aromatic ring may be substituted with CN .)
(2) Item (1) above, characterized in that it contains at least one organic residue derived from a diamino compound selected from the group of groups represented by formula (2) to formula (5). The polyamideimide described in 1.

(Wherein R ⁴ is H or alkyl having 1 to 12 carbon atoms, ring A is 1,4-phenylene or 1,4-cyclohexylene, and Z ¹ and Z ² are each independently a single bond, CH ₂ , CH ₂ CH ₂ or O, r is 0 to 3, s is 0 to 5, t1 is 0 to 3, t2 is an integer of 0 to 3, but t1 is 2 to 3 Z ¹ may be the same as or different from each other, and the plurality of Z ² when t 2 is 2 to 3 may be the same as or different from each other. Arbitrary H of 4-phenylene or 1,4-cyclohexylene may be substituted with alkyl having 1 to 4 carbon atoms.)

(Wherein, X ¹ and X ² are each independently a single bond, O, COO, OCO, NH, CONH or alkylene having 1 to 12 carbon atoms, and G ¹ and G ² are each independently a single bond, Or a binary group containing 1 to 3 rings selected from an aromatic ring and an alicyclic ring, and R ⁵ is H, F, CN, OH or an alkyl, fluoroalkyl or alkoxy having 1 to 12 carbon atoms And the position of the substituent on the benzene ring and the position of the two free radicals are arbitrary, provided that when G ² is a single bond and X ² is neither a single bond nor alkylene, R ⁵ Is H or alkyl, and when G ¹ and G ² are both a single bond, the total carbon number of X ¹ , X ² and R ⁵ is 3 or more.)

(Wherein X ³ and X ⁴ are each independently a single bond, CH ₂ , CH ₂ CH ₂ or O, and R ⁶ and R ⁷ are each independently H, alkyl having 1 to 12 carbons, or A perfluoroalkyl having 1 to 12 carbon atoms, wherein at least one of R ⁶ and R ⁷ is an alkyl or perfluoroalkyl having 3 or more carbon atoms, and u1 and u2 are each independently an integer of 0 to 3 However, the plurality of X ³ when u1 is 2 to ³ may be the same or different from each other, and the plurality of X ⁴ when u2 is 2 to 3 are also the same as each other. And any H in 1,4-phenylene may be substituted with alkyl having 1 to 4 carbon atoms.)

(In the formula, R ⁸ is H, or linear or branched alkyl having 1 to 12 carbon atoms, and one or a plurality of non-adjacent CH ₂ in the alkyl may be substituted with O; X ⁵ is a single bond or alkylene having 1 to 5 carbon atoms, and one or a plurality of non-adjacent CH ₂ in the alkylene may be substituted with O, and m is an integer of 0 to 3. , N is an integer of 1 to 5. The bonding position of the substituent and the free radical to the benzene ring is an arbitrary position.
(3) R ¹ , R ² and R ³ are each independently H or a monovalent organic group having 5 or less carbon atoms, and 50 mol% or more of the total amount of R ^{1 to} R ^{3 is} the monovalent organic group The polyamide-imide according to item (1) or (2), which is a group.
(4) R ¹ , R ² and R ³ are each independently H, alkyl having 5 or less carbon atoms or oxygen-containing alkyl having 5 or less carbon atoms, and 70 mol% or more of the total amount of R ^{1 to} R ³ is The polyamideimide according to (1) or (2) above, which is a monovalent organic group selected from these alkyls and oxygen-containing alkyls.
(5) A liquid crystal aligning agent varnish comprising the polyamideimide described in any one of (1) to (4).
(6) A liquid crystal display element using the liquid crystal aligning agent varnish described in the above item (5).
The polyamideimide of the present invention having the above-described configuration can be used as an alignment film, a protective film, an insulating film, etc., and is particularly suitable as an alignment agent varnish for forming an alignment film for a liquid crystal display element. And the polyamideimide of this invention can further improve characteristics, such as an orientation agent varnish, by using together with other high molecular compounds, such as a polyamic acid, soluble polyimide, and polyamide.

The polyamideimide of the present invention has a structure represented by the formula (1-1) among structural units represented by the following formulas (1-1), (1-2), and (1-3). It is a polyamideimide having only units or two or more of these three structural units, and contains at least one organic residue having a side chain group having 3 or more carbon atoms. It is a characteristic polyamideimide. That is, it is a compound having both an amide bond and an imide bond in the molecule and containing at least one organic residue having a side chain group having 3 or more carbon atoms, and a part of hydrogen atoms of the amide bond (CONH) Alternatively, it is a polyamideimide substituted entirely with a monovalent organic group (hereinafter sometimes referred to as N-substituted polyamideimide).

T ¹ in the structural unit represented by the formula (1-1) is an organic residue derived from tricarboxylic acids, and T ² in the structural unit represented by the formula (1-2) is derived from dicarboxylic acids. T ³ in the structural unit represented by the formula (1-3) is an organic residue derived from tetracarboxylic acids. In the present invention, dicarboxylic acid, tricarboxylic acid, tetracarboxylic acid, and polyvalent carboxylic acid, which is a name when these are collectively called, are generic names including anhydrides, acid halides, etc., which are derivatives thereof. They are referred to as dicarboxylic acids, tricarboxylic acids, tetracarboxylic acids and polycarboxylic acids, respectively. These polyvalent carboxylic acids may belong to any group of aromatic (including heterocycle), alicyclic (including heterocycle) or aliphatic (non-cyclic), Among them, those having a ring structure are preferable from the viewpoint of maintaining good alignment of the liquid crystal. Therefore, when an aliphatic (non-cyclic) one is used, it is preferably used in combination with an alicyclic or aromatic one, and the amount used does not adversely affect the liquid crystal alignment. Should be within range. Further, T ^{1 to} T ³ are preferably those having a structure that does not contain groups such as ether, ester, thioether, and thioester, which are likely to cause deterioration of the electrical characteristics of the liquid crystal display element, Even if it has such a structure, there is no problem as long as these characteristics are not affected.

Specific examples of dicarboxylic acids that can be used in the polyamideimide of the present invention include the following compounds.
That is, malonic acid dihalide, oxalic acid dihalide, dimethylmalonic acid dihalide, succinic acid dihalide, fumaric acid dihalide, glutaric acid dihalide, adipic acid dihalide, muconic acid dihalide, 2-methyladipic acid dihalide, trimethyladipic acid dihalide, pimelic acid dihalide, Aliphatic dicarboxylic acid dihalides such as 2,2-dimethylglutaric acid dihalide, 3,3-diethylsuccinic acid dihalide, azeraiic acid dihalide, sebacic acid dihalide and suberic acid dihalide;

  1,1-cyclopropanedicarboxylic acid dihalide, 1,2-cyclopropanedicarboxylic acid dihalide, 1,1-cyclobutanedicarboxylic acid dihalide, 1,2-cyclobutanedicarboxylic acid dihalide, 1,3-cyclobutanedicarboxylic acid dihalide, 3,4 -Diphenyl-1,2-cyclobutanedicarboxylic acid dihalide, 2,4-diphenyl-1,3-cyclobutanedicarboxylic acid dihalide, 3,4-bis (2-hydroxyphenyl) -1,2-cyclobutanedicarboxylic acid dihalide, 2, 4-bis (2-hydroxyphenyl) -1,3-cyclobutanedicarboxylic acid dihalide, 1-cyclobutene-1,2-dicarboxylic acid dihalide, 1-cyclobutene-3,4-dicarboxylic acid dihalide, 1,1-cyclopentanedicarboxylic acid Acid dihalides, , 2-cyclopentanedicarboxylic acid dihalide, 1,3-cyclopentanedicarboxylic acid dihalide, 1,1-cyclohexanedicarboxylic acid dihalide, 1,2-cyclohexanedicarboxylic acid dihalide, 1,3-cyclohexanedicarboxylic acid dihalide, 1,4- Cyclohexanedicarboxylic acid dihalide, 1,4- (2-norbornene) dicarboxylic acid dihalide, norbornene-2,3-dicarboxylic acid dihalide, bicyclo [2.2.2] octane-1,4-dicarboxylic acid dihalide, bicyclo [2. 2.2] octane-2,3-dicarboxylic acid dihalide, 2,5-dioxo-1,4-bicyclo [2.2.2] octane dicarboxylic acid dihalide, 1,3-adamantane dicarboxylic acid dihalide, 4,8- Dioxo-1,3-adamantanji Carboxylic acid dihalide, 2,6-spiro [3.3] heptane dicarboxylic acid dihalide, 1,3-adamantane diacetic acid dihalides, dihalide alicyclic dicarboxylic acids such as camphor acid dihalides;

  o-phthalic acid dihalide, isophthalic acid dihalide, terephthalic acid dihalide, 5-methylisophthalic acid dihalide, 5-tert-butylisophthalic acid dihalide, 5-aminoisophthalic acid dihalide, 5-hydroxyisophthalic acid dihalide, 2,5-dimethylterephthalic acid Acid dihalide, tetramethylterephthalic acid dihalide, 1,4-naphthalenedicarboxylic acid dihalide, 2,5-naphthalenedicarboxylic acid dihalide, 2,6-naphthalenedicarboxylic acid dihalide, 2,7-naphthalenedicarboxylic acid dihalide, 1,4-anthracene Dicarboxylic acid dihalide, 1,4-anthraquinone dicarboxylic acid dihalide, 2,5-biphenyldicarboxylic acid dihalide, 4,4′-biphenyldicarboxylic acid dihalide, 1,5-biphenylene dica Boronic acid dihalide, 4,4 "-terphenyldicarboxylic acid dihalide, 4,4'-diphenylmethanedicarboxylic acid dihalide, 4,4'-diphenylethanedicarboxylic acid dihalide, 4,4'-diphenylpropanedicarboxylic acid dihalide, 4, 4'-diphenylhexafluoropropane dicarboxylic acid dihalide, 4,4'-diphenyl ether dicarboxylic acid dihalide, 4,4'-bibenzyldicarboxylic acid dihalide, 4,4'-stilbene dicarboxylic acid dihalide, 4,4'-transicarboxylic acid Dihalide, 4,4′-carbonyldibenzoic acid dihalide, 4,4′-sulfonyldibenzoic acid dihalide, 4,4′-dithiodibenzoic acid dihalide, p-phenylenediacetic acid dihalide, 3,3′-p-pheny Range propionic acid dihalide 4-carboxycinnamic acid dihalide, p-phenylenediacrylic acid dihalide, 3,3 ′-(4,4 ′-(methylenedi-p-phenylene)) dipropionic acid dihalide, 4,4 ′-(4,4′- (Oxydi-p-phenylene)) dipropionic acid dihalide, 4,4 '-(4,4'-(oxydi-p-phenylene)) dibutyric acid dihalide, (isopropylidenedi-p-phenylenedioxy) dibutyric acid dihalide Bis (p-carboxyphenyl) dimethylsilane, 1,5- (9-oxofluorene) dicarboxylic acid dihalide, 3,4-furandicarboxylic acid dihalide, 4,5-thiazole dicarboxylic acid dihalide, 2-phenyl-4,5 -Thiazole dicarboxylic acid dihalide, 1,2,5-thiadiazole-3,4-dicarboxylic acid dihalide, 1,2 , 5-oxadiazole-3,4-dicarboxylic acid dihalide, 2,3-pyridinedicarboxylic acid dihalide, 2,4-pyridinedicarboxylic acid dihalide, 2,5-pyridinedicarboxylic acid dihalide, 2,6-pyridinedicarboxylic acid dihalide 3,4-pyridinedicarboxylic acid dihalide, 3,5-pyridinedicarboxylic acid dihalide, and 6-pyridinedicarboxylic acid dihalide.

  The dicarboxylic acids for producing the N-substituted polyamideimide of the present invention are not limited to these dicarboxylic acid dihalides, and organic residues derived from dicarboxylic acids in the structural unit represented by the formula (1-2) are used. Other forms of dicarboxylic acid derivatives may be used if provided. Examples of such a dicarboxylic acid derivative include an active acyl derivative. For example, a dicarboxylic acid derivative to which a group such as acetyloxy, alkyloxy, phenyloxy or phenylthio is bonded may be used instead of the halogen of the dicarboxylic acid dihalide. it can. Furthermore, dicarboxylic acid itself in which H of the carboxyl group is not substituted at all can also be used. The dicarboxylic acids used in the present invention are preferably dicarboxylic acids that can give a polyamideimide having a linear structure from the viewpoint of maintaining the orientation of the liquid crystal. Examples of such preferred dicarboxylic acids include 1,4-cyclohexanedicarboxylic acid dihalide, terephthalic acid dihalide, isophthalic acid dihalide, pyridinedicarboxylic acid dihalide, naphthalenedicarboxylic acid dihalide, 1,4-anthracene dicarboxylic acid dihalide, 4,4 ′. -Biphenyldicarboxylic acid dihalide, 4,4 "-terphenyldicarboxylic acid dihalide, 4,4'-diphenylmethanedicarboxylic acid dihalide, 4,4'-diphenylethanedicarboxylic acid dihalide, 4,4'-diphenylpropanedicarboxylic acid dihalide, 4,4'-diphenylhexafluoropropane dicarboxylic acid dihalide, 4'-diphenyl ether dicarboxylic acid dihalide, etc. As mentioned above, the same residues as these compounds can be mentioned. Give a compound of type other than the acid dihalide is also preferably used.

（式中、Ｒ^９およびＲ^１０はそれぞれ独立してメチル、エチル、フェニルまたはシクロヘキシルであり、Ｘはハロゲンであり、ｖ、ｗおよびｘはそれぞれ独立して１〜５の整数である。）In addition, for the purpose of increasing the adhesion of polyamideimide to the substrate, etc., using polysiloxane dicarboxylic acid dihalide represented by formula (6) or an active acyl derivative other than acid dihalide which gives the same residue as this. Also good. In some cases, a compound in which X in Formula (6) is H may be used.

(Wherein R ⁹ and R ¹⁰ are each independently methyl, ethyl, phenyl or cyclohexyl, X is a halogen, and v, w and x are each independently an integer of 1 to 5)

（式中、Ｘ^６は単結合、Ｏ、ＣＯＯ、ＯＣＯ、ＮＨ、ＮＨＣＯ、ＣＯＮＨ、Ｓまたは炭素数１〜６のアルキレンであり、Ｘはハロゲンであり、Ｒ^１１は炭素数３〜２０のアルキルもしくはフルオロアルキル基、または置換基を有しても良いステロイド基である。ステロイド骨格としては、コレステリル、アンドロステリル、βコレステリル、エピアンドロステリル、エリゴステリル、エストリル、１１α−ヒドロキシメチルステリル、１１α−プロゲステリル、ラノステリル、メラトラニル、メチルテストロステリル、ノレチステリル、プレグネノニル、β−シトステリル、スチグマステリル、テストステリル、酢酸コレステロールエステル等を挙げることが出来る。）The N-substituted polyamideimide of the present invention has at least one organic residue having a side chain group having 3 or more carbon atoms, and thereby has a function of developing a large pretilt angle in the liquid crystal. Then, the introduction of the organic residue having a side chain group having 3 or more carbon atoms gives the dicarboxylic acid dihalide represented by the formula (7) or the formula (8), or the same residue as that other than the acid dihalide. You may carry out by using an active acyl derivative. Furthermore, compounds in which X is H in these formulas can also be used.

(In the formula, X ⁶ is a single bond, O, COO, OCO, NH, NHCO, CONH, S or alkylene having 1 to 6 carbon atoms, X is halogen, and R ¹¹ is alkyl having 3 to 20 carbon atoms. Alternatively, it is a fluoroalkyl group or a steroid group which may have a substituent, and examples of the steroid skeleton include cholesteryl, androsteryl, β-cholesteryl, epiandrosteryl, erygosteryl, estryl, 11α-hydroxymethylsteryl, 11α-progesteryl. , Lanosteryl, melatranyl, methyltestrosteryl, norethisteryl, pregnenoyl, β-sitosteryl, stigmasteryl, testosteryl, acetic acid cholesterol ester, etc.)

（式中、Ｒ^１２およびＲ^１３はそれぞれ独立して炭素数１〜１２のアルキルであるが、それらの炭素数の合計は４以上であり、Ｘはハロゲンである。）
本発明のＮ置換ポリアミドイミドの製造に使用できるジカルボン酸類は、上記の例示化合物に限定されることはなく、またこれらを２種以上組み合わせて用いることもできる。

(In the formula, R ¹² and R ¹³ are each independently alkyl having 1 to 12 carbons, but the total of these carbons is 4 or more, and X is halogen.)
The dicarboxylic acids that can be used in the production of the N-substituted polyamideimide of the present invention are not limited to the above exemplary compounds, and two or more of these can be used in combination.

  Next, as a part of specific examples of the tricarboxylic acids that can be used for the production of the N-substituted polyamideimide of the present invention, the following tricarboxylic acid anhydride halides can be mentioned.

（これらの式中のＸはハロゲン原子を示す。）

(X in these formulas represents a halogen atom.)

  The tricarboxylic acids for producing the N-substituted polyamideimide of the present invention are not limited to these tricarboxylic anhydride halides, and organic residues derived from tricarboxylic acids in the structural unit represented by the formula (1-1) are used. All tricarboxylic acids providing groups are included. Further, in place of the halogen of the tricarboxylic acid anhydride halide, an active acyl derivative other than halide to which a group such as acetyloxy, alkyloxy, phenyloxy or phenylthio is bonded may be used. Furthermore, a compound in which two carboxyl groups of tricarboxylic acid are dehydrated and condensed to form an anhydride structure, and the remaining one is a carboxyl group, or tricarboxylic acid itself can be used. Among these, trimellitic anhydride halide of the formula (9) is preferably used. These tricarboxylic acids can also be used in combination of two or more.

As a part of specific examples of tetracarboxylic acids that can be used in the production of the N-substituted polyamideimide of the present invention, the following compounds can be mentioned.
First, as examples of alicyclic tetracarboxylic dianhydrides, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,5,6-cyclohexanetetracarboxylic dianhydride, bicyclo (2,2,2) -oct (7) -ene-2,3,5,6-tetracarboxylic dianhydride, 3,3 '-Bicyclohexyl-1,1', 2,2'-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 5- (2,5-dioxotetrahydrofural) -3 -Methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5-tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1, 2, -c] -furan-1,3 Dione, 3,5,6-tricarboxynorbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride and the like, and a part of H bonded to the ring of these compounds. Examples thereof include compounds substituted with lower alkyl such as methyl and ethyl.

  Next, as examples of aliphatic tetracarboxylic acids, ethylenetetracarboxylic dianhydride, butanetetracarboxylic dianhydride, pentanetetracarboxylic dianhydride, hexanetetracarboxylic dianhydride, heptanetetracarboxylic acid A dianhydride etc. can be mentioned.

  Examples of aromatic tetracarboxylic acids include pyromellitic dianhydride, 3, 3 ′, 4,4′-diphenyltetracarboxylic dianhydride, 3,3 ′, 4, 4′-benzophenone tetra Carboxylic dianhydride, 2,3,6,7-naphthalene dianhydride, 3,3'-4,4'-biphenylsulfone tetracarboxylic dianhydride, 3,3 ', 4,4'-biphenyl Ether tetracarboxylic dianhydride, 3,3 ′, 4,4′-dimethyldiphenylsilane tetracarboxylic dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenyl sulfide dianhydride 4,4′-bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ′, 4, '-Perfluoropyridene diphthalic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylsulfin oxide dianhydride, p-phenylene-bis (tri Phenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4′-diphenyl ether dianhydride, bis (triphenylphthalic acid) ) -4,4'-diphenylmethane dianhydride.

  Among these, cyclobutanetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, tricarboxycyclopentylacetic acid dianhydride, cyclohexanetetracarboxylic dianhydride, butanetetracarboxylic dianhydride, pyromellitic acid dianhydride An anhydride or the like can be particularly preferably used. The tetracarboxylic acids for producing the N-substituted polyamideimide of the present invention are not limited to these tetracarboxylic dianhydrides, and are derived from the tetracarboxylic acids in the structural unit represented by the formula (1-3) All tetracarboxylic acids which give organic residues are included. In addition, other types of tetracarboxylic acids other than dianhydrides may be used. For example, two carboxyl groups of tetracarboxylic acid are dehydrated and condensed to become anhydrides, and H of the remaining carboxyl groups is halogen, acetyloxy, Derivatives substituted with a group such as alkyloxy, phenyloxy or phenylthio, and derivatives where all H of four carboxyl groups of tetracarboxylic acid are substituted with the above groups can be used. Furthermore, tetracarboxylic acid itself in which H of the carboxyl group is not substituted can also be used. Moreover, these tetracarboxylic acids can also be used in combination of 2 or more types.

As described above, the N-substituted polyamideimide of the present invention has at least one organic residue having a side chain group having 3 or more carbon atoms, and is thereby given a function of developing a large pretilt angle in the liquid crystal. ing. The organic residue having a side chain group having 3 or more carbon atoms may be an organic residue derived from carboxylic acid, an organic residue derived from diamine, or both of them. There may be. That is, it is an N-substituted polyamideimide containing a structural unit represented by the formula (1-1), not including a structural unit represented by the formula (1-2) or a structural unit represented by the formula (1-3). In some cases, T ¹ which is an organic residue derived from tricarboxylic acids and / or D ¹ which is an organic residue derived from diamine needs to be an organic residue having a side chain group having 3 or more carbon atoms. D ¹ is preferably an organic residue having a side chain group having 3 or more carbon atoms, and both D ¹ and T ¹ may be an organic residue having a side chain group having 3 or more carbon atoms. .

In the case of an N-substituted polyamideimide containing a structural unit represented by the formula (1-1) and a structural unit represented by the formula (1-2), T ¹ which is an organic residue derived from tricarboxylic acids, It is necessary that at least one of T ² which is an organic residue derived from dicarboxylic acids and D ¹ and D ² which are organic residues derived from diamine is an organic residue having a side chain group having 3 or more carbon atoms. . Then, it is preferable that at least one of D ¹ and D ² is an organic residue having 3 or more side groups carbons, T ² also together with further at least one of D ¹ and D ^2, carbon It may be an organic residue having a side chain group of several or more.

In the case of an N-substituted polyamideimide containing a structural unit represented by the formula (1-1) and a structural unit represented by the formula (1-3), T ¹ which is an organic residue derived from tricarboxylic acids, It is necessary that at least one of T ³ which is an organic residue derived from tetracarboxylic acids and D ¹ and D ³ which are organic residues derived from diamine is an organic residue having a side chain group having 3 or more carbon atoms. is there. Then, it is preferred that at least one of D ¹ and D ³ is an organic residue having 3 or more side groups carbons.

In the case of an N-substituted polyamideimide containing a structural unit represented by the formula (1-2) and a structural unit represented by the formula (1-3), T ² which is an organic residue derived from dicarboxylic acids, At least one of T ³ which is an organic residue derived from tetracarboxylic acids and D ² and D ³ which are organic residues derived from diamine needs to be an organic residue having a side chain group having 3 or more carbon atoms. is there. Then, it is preferable that at least one of D ² and D ³ is an organic residue having 3 or more side groups carbons, T ² also together with further at least one of D ² and D ^3, carbon It may be an organic residue having a side chain group of several or more.

When the N-substituted polyamideimide includes a structural unit represented by formula (1-1), a structural unit represented by formula (1-2), and a structural unit represented by formula (1-3) Are T ¹ which is an organic residue derived from tricarboxylic acids, T ² which is an organic residue derived from dicarboxylic acids, T ³ which is an organic residue derived from tetracarboxylic acids, and D ¹ which is an organic residue derived from diamine. At least one of D ³ needs to be an organic residue having a side chain group having 3 or more carbon atoms. ^Then, it is preferable that at least one of D 1 to D ³ is an organic residue having 3 or more side groups carbons, ^{T 2} also together with further at least one of ^D 1 to D ^3, carbon It may be an organic residue having a side chain group of several or more.

  The diamino compound that can be used for the production of the N-substituted polyamideimide of the present invention is an aromatic system (including a heterocyclic ring system), an alicyclic system (including a heterocyclic ring) or an aliphatic system (including a heterocyclic ring), as in the above-described carboxylic acids. Any of those belonging to any one of (non-cyclic) is preferable, but those having a ring structure are preferable from the viewpoint of maintaining good alignment of the liquid crystal. In addition, these diamino compounds generally have a structure in which the organic residue does not contain a group such as ether, ester, thioether, thioester, etc., which tends to deteriorate the electrical characteristics of the liquid crystal display element. However, even if it has such a structure, there is no problem as long as these characteristics are not affected.

The diamino compound used in the production of the N-substituted polyamideimide of the present invention can be a diamino compound having no side chain when the organic residue derived from carboxylic acids has a side chain group having 3 or more carbon atoms, Even in this case, it is preferable to use together a carboxylic acid having a side chain group having 3 or more carbon atoms and a diamino compound having a side chain group having 3 or more carbon atoms. In addition, when carboxylic acids having a side chain group having 3 or more carbon atoms are not used, it is essential to use a diamino compound having a side chain group having 3 or more carbon atoms. In this case, as a side chain group having 3 or more carbon atoms, an aliphatic hydrocarbon group, a hydrocarbon group containing an alicyclic structure, a hydrocarbon group containing an aromatic group, a group having a siloxane group, a group having a steroid skeleton, Or the side chain group in which these structures are mixed can be mentioned. The alicyclic hydrocarbon group or aromatic hydrocarbon group may have a substituent such as alkyl, alkoxy, halogen, and OH. Some of these hydrocarbons may be substituted with other atoms such as oxygen, but do not include oxygen atoms, sulfur atoms, or groups containing these, such as O, CO, COO, S, SO _2, etc. Is preferred. In addition, about carbon number of a side chain group, when cyclic structures, such as a cyclohexane, are included, it shall represent with the number including carbon which comprises the ring.

（式中、Ｒ^４はＨまたは炭素数１〜１２のアルキルであり、環Ａは１，４−フェニレンまたは１，４−シクロヘキシレンであり、Ｚ^１およびＺ^２はそれぞれ独立して単結合、ＣＨ_２、ＣＨ_２ＣＨ_２またはＯであり、ｒは０〜３、ｓは０〜５、ｔ１は０〜３、ｔ２は０〜３のそれぞれ整数であるが、ｔ１が２〜３である時の複数のＺ^１は互いに同じであっても異なっていてもよいし、またｔ２が２〜３である時の複数のＺ^２も互いに同じであっても異なっていてもよい。また、１，４−フェニレンまたは１，４−シクロヘキシレンの任意のＨは炭素数１〜４のアルキルで置換されていてもよい。）The diamino compound having a side chain group having 3 or more carbon atoms, which can be preferably used for the production of the N-substituted polyamideimide of the present invention, gives an organic residue represented by each of the formulas (2) to (5). A compound. The N-substituted polyamideimide of the present invention preferably contains at least one residue selected from the group of these organic residues.

(Wherein R ⁴ is H or alkyl having 1 to 12 carbon atoms, ring A is 1,4-phenylene or 1,4-cyclohexylene, and Z ¹ and Z ² are each independently a single bond, CH ₂ , CH ₂ CH ₂ or O, r is 0 to 3, s is 0 to 5, t1 is 0 to 3, t2 is an integer of 0 to 3, but t1 is 2 to 3 Z ¹ may be the same as or different from each other, and the plurality of Z ² when t 2 is 2 to 3 may be the same as or different from each other. Arbitrary H of 4-phenylene or 1,4-cyclohexylene may be substituted with alkyl having 1 to 4 carbon atoms.)

（式中、Ｘ^１およびＸ^２はそれぞれ独立して単結合、Ｏ、ＣＯＯ、ＯＣＯ、ＮＨ、ＣＯＮＨまたは炭素数１〜１２のアルキレンであり、Ｇ^１およびＧ^２はそれぞれ独立して単結合、または芳香族環および脂環式環から選ばれる１〜３個の環を含む二価の基であり、Ｒ^５はＨ、Ｆ、ＣＮ、ＯＨまたは炭素数１〜１２のアルキル、フルオロアルキルもしくはアルコキシであり、ベンゼン環に対する置換基の結合位置および２個の遊離基の位置は任意の位置である。但し、Ｇ^２が単結合でありＸ^２が単結合でもなくアルキレンでもない場合は、Ｒ^５はＨまたはアルキルであり、またＧ^１およびＧ^２が共に単結合である場合は、Ｘ^１、Ｘ^２およびＲ^５の合計の炭素数が３以上である。）

(Wherein, X ¹ and X ² are each independently a single bond, O, COO, OCO, NH, CONH or alkylene having 1 to 12 carbon atoms, and G ¹ and G ² are each independently a single bond, Or a divalent group containing 1 to 3 rings selected from an aromatic ring and an alicyclic ring, and R ⁵ is H, F, CN, OH or an alkyl, fluoroalkyl or alkoxy having 1 to 12 carbon atoms And the position of the substituent on the benzene ring and the position of the two free radicals are arbitrary, provided that when G ² is a single bond and X ² is neither a single bond nor alkylene, R ⁵ Is H or alkyl, and when G ¹ and G ² are both a single bond, the total carbon number of X ¹ , X ² and R ⁵ is 3 or more.)

（式中、Ｘ^３およびＸ^４はそれぞれ独立して単結合、ＣＨ_２、ＣＨ_２ＣＨ_２またはＯであり、Ｒ^６およびＲ^７はそれぞれ独立してＨ、炭素数１〜１２のアルキル、または炭素数１〜１２のパーフルオロアルキルであるが、Ｒ^６およびＲ^７の少なくとも一方は炭素数３以上のアルキルまたはパーフルオロアルキルであり、ｕ１およびｕ２はそれぞれ独立して０〜３の整数であるが、ｕ１が２〜３である時の複数のＸ^３は互いに同じであっても異なっていてもよいし、ｕ２が２〜３である時の複数のＸ^４も互いに同じであっても異なっていてもよい。また、１，４−フェニレンの任意のＨは炭素数１〜４のアルキルで置換されていてもよい。）

(Wherein X ³ and X ⁴ are each independently a single bond, CH ₂ , CH ₂ CH ₂ or O, and R ⁶ and R ⁷ are each independently H, alkyl having 1 to 12 carbons, or Perfluoroalkyl having 1 to 12 carbon atoms, at least one of R ⁶ and R ⁷ is alkyl or perfluoroalkyl having 3 or more carbon atoms, and u1 and u2 are each independently an integer of 0 to 3 However, when u1 is 2 to 3, the plurality of X ³ may be the same or different from each other, and when u2 is 2 to 3, the plurality of X ⁴ are also the same or different from each other. In addition, any H of 1,4-phenylene may be substituted with alkyl having 1 to 4 carbon atoms.)

（式中、Ｒ^８はＨ、または炭素数１〜１２の直鎖もしくは分岐状のアルキルであり、このアルキル中の１個もしくは隣り合わない複数のＣＨ_２はＯで置換されていてもよく、Ｘ^５は単結合、または炭素数１〜５のアルキレンであり、このアルキレン中の１個もしくは隣り合わない複数のＣＨ_２はＯで置換されていてもよく、ｍは０〜３の整数であり、ｎは１〜５の整数である。また、ベンゼン環に対する置換基および遊離基の結合位置は任意の位置である。）

(In the formula, R ⁸ is H, or linear or branched alkyl having 1 to 12 carbon atoms, and one or a plurality of non-adjacent CH ₂ in the alkyl may be substituted with O; X ⁵ is a single bond or alkylene having 1 to 5 carbon atoms, and one or a plurality of non-adjacent CH ₂ in the alkylene may be substituted with O, and m is an integer of 0 to 3. , N is an integer of 1 to 5. The bonding position of the substituent and the free radical to the benzene ring is an arbitrary position.

（式中のＲ^４、Ａ、Ｚ^１、Ｚ^２、ｒ、ｓ、ｔ１およびｔ２の意味は、式（２）における場合と同じである。）
この式（１７）で表されるジアミノ化合物の具体例の一部を、Ｒ^４、環Ａ、Ｚ、ｒ、ｓおよびｔの組み合わせによって、表１〜表５に示す。なお、Ｚ^１＝Ｚ^２＝Ｚであり、ｔ１＝ｔ２＝ｔである。また、これらの表の環Ａの欄に記載されたＢは１，４−フェニレン、Ｃｈは１，４−ジクロヘキシレンを示す。The diamino compound giving the organic residue represented by the formula (2) is represented by the formula (17).

(In the formula, the meanings of R ⁴ , A, Z ¹ , Z ² , r, s, t 1 and t 2 are the same as in the formula (2).)
A part of specific examples of the diamino compound represented by the formula (17) are shown in Tables 1 to 5 depending on combinations of R ⁴ , rings A, Z, r, s, and t. Note that Z ¹ = Z ² = Z and t1 = t2 = t. Further, B described in the column of ring A in these tables represents 1,4-phenylene, and Ch represents 1,4-dichlorohexylene.

The diamino compound represented by the formula (17) is not limited to these exemplified compounds, and two or more kinds can be used in combination. In these diamino compounds, when r is 0 and R ⁴ is H or short-chain alkyl, a liquid crystal alignment film that gives a small pretilt angle to the liquid crystal is given. When r is 1 to 3, R ⁴ Even if H is H, a liquid crystal alignment film that gives a large pretilt angle to the liquid crystal is provided. A liquid crystal alignment film that develops a small pretilt angle is suitable for an IPS liquid crystal display element, and a pretilt angle of about 3 to 8 ° is suitable for a TN liquid crystal display element. Further, in the case of STN type liquid crystal display elements, VA type liquid crystal display elements and OCB type liquid crystal display elements, a larger pretilt angle may be required. In this case, a diamino compound having a long side chain group may be used. .

Furthermore, you may use the diamino compound which has a C3 or more side chain group as represented by each of Formula (18), Formula (19), and Formula (20).

(The meanings of Z ¹ , Z ² , t1 and t2 in these formulas are the same as in the formula (2), and R ¹⁴ and R ¹⁵ are each independently hydrogen or alkyl having 1 to 12 carbon atoms. Provided that any ring in the steroid skeletons of formula (18) and formula (19) may be reduced, expanded or cleaved, may be a bicyclo ring, and the unsaturated bond is increased at any position or It may be reduced, or H or alkyl at any position may be substituted with another monovalent organic group.)

（式中のＸ^１、Ｘ^２、Ｇ^１、Ｇ^２およびＲ^５の意味は式（３）における場合と同じであり、またベンゼン環に対する置換基および２個のアミノ基の結合位置は任意の位置である。）
式（２１）で表されるジアミノ化合物の具体例の一部を、Ｘ^１、Ｘ^２、Ｇ^１、Ｇ^２およびＲ^５の組み合わせによって、表６〜表１２に示す。これらの表においては、「−」は単結合、「Ｂ」は１，４−フェニレン、「Ｃｈ」は１，４−シク口ヘキシレンを示す。また、「Ｂ−Ｃｈ」、「Ｃｈ−Ｂ」、「Ｂ−Ｃｈ−Ｃｈ」などは、環の種類と結合の順序を示す。例えば、Ｇ^１の欄のＢ−Ｃｈは、Ｘ^１に１，４−フェニレンが結合し、この１，４−フェニレンに結合した１，４−シクロヘキシレンにＸ^２が結合していることを意味し、Ｇ^２の欄のＣｈ−Ｂは、Ｘ_２に１，４−シクロヘキシレンが結合し、この１，４−シクロヘキシレンに結合した１，４−フェニレンにＲ^５が結合していることを意味する。なお、これらの表に記載した化合物は１，３−ジアミノベンゼン誘導体であり、Ｘ^１がジアミノベンゼンの５位に結合したジアミノ化合物である。The diamino compound that gives the organic residue represented by the formula (3) is represented by the formula (21).

(In the formula, the meanings of X ¹ , X ² , G ¹ , G ² and R ⁵ are the same as in the formula (3), and the substituents on the benzene ring and the bonding positions of the two amino groups are arbitrary. Position.)
A part of specific examples of the diamino compound represented by the formula (21) are shown in Tables 6 to 12 according to combinations of X ¹ , X ² , G ¹ , G ² and R ⁵ . In these tables, “-” represents a single bond, “B” represents 1,4-phenylene, and “Ch” represents 1,4-diethylhexylene. “B-Ch”, “Ch-B”, “B-Ch-Ch”, and the like indicate the type of ring and the order of bonding. For example, B-Ch in the column of G ¹ means that 1,4-phenylene is bonded to X ¹ and X ² is bonded to 1,4-cyclohexylene bonded to 1,4-phenylene. In the column G ² , Ch-B indicates that 1,4-cyclohexylene is bonded to X ₂ and R ⁵ is bonded to 1,4-phenylene bonded to 1,4-cyclohexylene. means. The compounds described in these tables are 1,3-diaminobenzene derivatives, and X ¹ is a diamino compound bonded to the 5-position of diaminobenzene.

The diamino compound represented by the formula (21) is not limited to these exemplified compounds, and two or more kinds can be used in combination. In these diamino compounds, when G ¹ and / or G ² has a large number of rings, X ¹ and / or X ² is a long-chain alkylene, and R ⁵ is a long-chain alkyl, fluoroalkyl or alkoxy, A liquid crystal alignment film that gives a large pretilt angle to the liquid crystal is provided.

（式中のＸ^３、Ｘ^４、Ｒ^６、Ｒ^７、ｕ１およびｕ２の意味は、式（４）における場合と同じである。）
式（２２）で表されるジアミノ化合物の具体例の一部を、式（２２）においてＸ^４＝Ｘ^３であり、ｕ２＝ｕ１である場合について、Ｘ^３、ｕ１、Ｒ^６およびＲ^７の組み合わせによって、表１３〜表１９に示す。なお、これらの表において、「−」は単結合を示す。The diamino compound giving the organic residue represented by the formula (4) is represented by the formula (22).

(The meanings of X ³ , X ⁴ , R ⁶ , R ⁷ , u1 and u2 in the formula are the same as in the formula (4).)
A part of specific examples of the diamino compound represented by the formula (22) are represented by the formulas of X ³ , u1, R ⁶ and R ^{7 in} the case where X ⁴ = X ³ and u2 = u1 in the formula (22). Table 13 to Table 19 show the combinations. In these tables, “-” represents a single bond.

The diamino compound represented by the formula (22) is not limited to these exemplified compounds, and two or more kinds can be used in combination. In these diamino compounds, when R ⁶ and R ⁷ are hydrogen, or short-chain alkyl or perfluoroalkyl, the liquid crystal aligning agent of the present invention obtained by using the diamino compound has a small pretilt angle in the liquid crystal. Gives a liquid crystal alignment film

（式中のＸ^５、Ｒ^８、ｍおよびｎの意味は、式（５）における場合と同じであり、ベンゼン環に対する置換基およびアミノ基の結合位置は任意の位置である。）
式（２３）で表されるジアミノ化合物の具体例の一部を、Ｘ^５、Ｒ^８、ｍおよびｎの組み合わせによって、表２０〜表２１に示す。なお、これらの表において、「−」は単結合を示す。また、これらの表に記載のジアミノ化合物は、２個のアミノ基がそれぞれベンゼン環のメチレン基の結合位置に対してパラ位に結合し、シクロヘキシレンが同じくオルソ位に結合している化合物である。The diamino compound giving the organic residue represented by the formula (5) is represented by the formula (23).

(The meanings of X ⁵ , R ⁸ , m and n in the formula are the same as in the formula (5), and the bonding position of the substituent and amino group to the benzene ring is an arbitrary position.)
A part of specific examples of the diamino compound represented by the formula (23) are shown in Tables 20 to 21 by combinations of X ⁵ , R ⁸ , m and n. In these tables, “-” represents a single bond. In addition, the diamino compounds described in these tables are compounds in which two amino groups are each bonded to the para position with respect to the bonding position of the methylene group of the benzene ring, and cyclohexylene is also bonded to the ortho position. .

The diamino compound represented by the formula (23) is not limited to these exemplified compounds, and two or more kinds can be used in combination. In these diamino compounds, when m is 0, R ⁸ is H or short-chain alkyl, and X ⁵ is a single bond or short-chain alkylene, the pretilt angle is small, and m is 1 to 3. In some cases, even if R ⁸ is H and X ⁵ is a single bond, the pretilt angle is increased.

  The above are only some of the diamino compounds that give organic residues represented by the formulas (2) to (5) as specific examples, and the carbon number according to the present invention. The diamino compound having 3 or more side chain groups is not limited thereto. In addition to these, for example, diamino compounds having a side chain group having 3 or more carbon atoms, such as a diamino compound in which a steroidal side chain is provided on phenylenediamine, are used on condition that the object of the present invention is achieved. Can be selected from a wide range.

  In the present invention, in order to adjust the pretilt angle to a required value, a diamino compound having a side chain group having 3 or more carbon atoms that is effective for increasing the pretilt angle of the liquid crystal (hereinafter referred to as the first group). And a diamino compound having no side chain group having 3 or more carbon atoms (hereinafter, sometimes referred to as a second group of diamino compounds) can be used in combination. Examples of the second group of diamino compounds that can be used in the present invention include aromatic diamino compounds, alicyclic diamino compounds, and aliphatic diamino compounds, which are described in many known literatures. You can choose from things. And as an example of well-known literature, the diamino compound as described in pages 19-20 and 34-37 of WO 01 / 00732A1 gazette can be mentioned. In addition, in connection with the diamino compounds described in this publication, those having different amino group bonding positions, those having different alkyl number and / or alkylene carbon number in the structure, and any H substituted with F And those in which the aromatic ring is substituted with a different number of alkyls. Furthermore, in addition to the above-mentioned diamino compounds, diamino compounds having a structure having an oxygen atom in alkylene can also be mentioned.

  As described above, the second group of diamino compounds used in the present invention can be arbitrarily selected from a great number of compounds and can be used in combination of two or more. However, the aliphatic group of the second group of diamino compounds is preferably used within a range in which the orientation of the liquid crystal is kept good. In order to keep the electrical properties of the liquid crystal display device high, it is preferable that the second group of diamino compounds have a structure that does not contain groups such as ether, ester, thioether, and thioester in the structure.

  In the production of the N-substituted polyamideimide of the present invention, when the first group of diamino compounds and the second group of diamino compounds are used in combination, the ratio of the two is the value of the type of compound used and the required pretilt angle. However, when expressed in molar ratio (diamino compound of the first group / diamino compound of the second group) (100/0) to (1/99), preferably (100/0) to ( 10/90), more preferably in the range of (100/0) to (20/80). Note that the pretilt angle increases as the proportion of the first diamino compound increases.

  The polyamideimide of the present invention is an N-substituted polyamideimide characterized in that 30 mol% or more of all amide bonds in the polymer are amide bonds in which a monovalent organic group is bonded to N. The monovalent organic group is a linear or branched alkyl having 1 to 20 carbon atoms, a linear or branched hydroxyalkyl having 1 to 8 carbon atoms, a linear or branched alkoxyalkyl having 2 to 20 carbon atoms, carbon It consists of an unsaturated aliphatic group having 2 to 15 groups, a group having an alicyclic group, an aromatic hydrocarbon group, a group having a steroid skeleton, a group having a carbonyl group, an organosilyl group, and an organosilyl group-containing group. One or more groups selected from the group. Arbitrary H in the alkyl may be substituted with F, and in the aromatic hydrocarbon group, an aromatic ring and alkyl or alkylene may be bonded via O. H of the alkyl which is a substituent of the aromatic ring may be substituted with F, and one H of the aromatic ring may be substituted with CN.

However, when a highly flexible group is used as the monovalent organic group, the liquid crystal alignment may be extremely deteriorated. Therefore, in consideration of the influence on the liquid crystal alignment, an organic group having 5 or less carbon atoms, particularly the carbon number. No more than 5 alkyls are preferred, and any CH ₂ in the alkyls may be substituted with O, CO or COO, as long as there are no 2 Os. However, this monovalent organic group may be any of the organic groups described above as long as there is no problem in liquid crystal alignment. And the substitution ratio by this monovalent organic group is preferably 50 mol% or more, and more preferably 70 mol% or more. By introducing the monovalent organic group into the polyamideimide, there is a great effect in improving the electrical characteristics particularly when used as a liquid crystal aligning agent varnish. In addition, the ratio of the monovalent organic group in the N-substituted polyamideimide must be 30 mol% or more in order to sufficiently exhibit the effect of improving the electrical characteristics of the liquid crystal display element.

  Specific examples of alkyl among such monovalent organic groups include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n -Decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, isopropyl, isobutyl, sec-butyl , Tert-butyl, isopentyl, neopentyl, tert-pentyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, isohexyl, 1-ethylpentyl, 2-ethylpentyl, 3-ethylpentyl, 4-ethylpentyl, 2,4-dimethylhexyl, 2,3,5-to Ethyl heptyl, trifluoromethyl, perfluoroethyl, n-perfluoropropyl, n-perfluorobutyl, n-perfluoropentyl, n-perfluorohexyl, n-perfluoroheptyl, n-perfluorooctyl, n-per Fluorononyl, n-perfluorodecyl, n-perfluoroundecyl, n-perfluorododecyl, n-perfluorotridecyl, n-perfluorotetradecyl, n-perfluoropentadecyl, n-perfluorohexadecyl, Examples thereof include n-perfluoroheptadecyl, n-perfluorooctadecyl, n-perfluorononadecyl, and n-perfluoroeicosyl.

  Specific examples of hydroxyalkyl include hydroxymethyl, hydroxyethyl, hydroxypropyl, hydroxybutyl, hydroxypentyl and hydroxyhexyl. Specific examples of alkoxyalkyl include methoxymethyl, methoxyethyl, methoxypropyl, methoxybutyl, methoxypentyl, methoxyhexyl and ethoxy. Specific examples of unsaturated aliphatic groups such as methyl, ethoxyethyl, ethoxypropyl, ethoxybutyl, ethoxypentyl, ethoxyhexyl, hexyloxymethyl, hexyloxyethyl, hexyloxypropyl, hexyloxybutyl, hexyloxypentyl and hexyloxyhexyl Examples include vinyl, ethynyl, 1-propenyl, 2-propenyl, isopropenyl, 2-butenyl, 1,3-butadienyl, - pentynyl, and 2-pentyne-4-yl, and 2-nonyl-2-butenyl, and the like,

  Specific examples of groups having an alicyclic group include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, bicyclohexyl, cyclopropylmethyl, cyclobutylmethyl, cyclopentylmethyl, cyclohexylmethyl, bicyclohexylmethyl, 2-cyclopenten-1-yl, and Specific examples of aromatic hydrocarbon groups such as 2,4-cyclopentadien-1-yl, phenyl, 2,6-dimethylphenyl, 2,6-diisopropylphenyl, biphenyl, triphenyl, terphenyl, benzyl, biphenylmethyl , Triphenylmethyl, terphenylmethyl, 4-methylbenzyl, 4- (tert-butyl) benzyl, α-methylbenzyl, 1-naphthyl, 2-naphthyl, 9-anthrylmethyl, 5-phenyl-2,4- Pentadiynyl 4-methoxybenzyl, phenoxymethyl, benzyloxymethyl, biphenyloxymethyl, naphthyloxymethyl, 4-trifluoromethylbenzyl, cyanophenyl, cyanobiphenyl, cyanoterphenyl, cyanobenzyl, cyanophenylmethyl, cyanobiphenylmethyl, and cyano Specific examples of O-containing heterocyclic groups such as terphenylmethyl include furfuryl, (3-furyl) methyl, 2-oxetanylmethyl, 3-oxetanylmethyl, oxolanylmethyl, and dioxolanylmethyl. it can.

  And then, as specific examples of a group having a steroid skeleton, cholesteryl, androsteryl, β-cholesteryl, epiandrosteryl, erygosteryl, estolyl, 11α-hydroxymethylsteryl, 11α-progesteryl, lanosteryl, melatranyl, methyltestosteryl, Specific examples of groups having a carbonyl group, such as norethisteryl, pregnonyl, β-sitosteryl, stigmasteryl, testosteryl, and acetic acid cholesterol ester, formyl, acetyl, benzoyl, methoxycarbonyl, phenylmethoxycarbonyl, etc., organosilyl and organosilyl-containing groups Specific examples of such include trimethylsilyl, triethylsilyl, triphenylsilyl, and 4-trimethylsilylbenzyl. .

  Among these, methyl, ethyl, n-propyl, n-butyl, n-pentyl, isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl, tert-pentyl, vinyl, ethynyl, 1-propenyl, 2-propenyl , Isopropenyl, 2-butenyl, 1,3-butadienyl, 2-pentenyl, 2-penten-4-yl, cyclopropyl, cyclobutyl, cyclopentyl, cyclopropylmethyl, cyclobutylmethyl, 2-cyclopenten-1-yl, 2 , 4-cyclopentadien-1-yl, trifluoromethyl, perfluoroethyl, methoxymethyl, methoxyethyl, methoxypropyl, methoxybutyl, ethoxymethyl, ethoxyethyl, ethoxypropyl, hydroxymethyl, hydroxyethyl Monovalent having 5 or less carbon atoms such as hydroxypropyl, hydroxybutyl, hydroxypentyl, furfuryl, (3-furyl) methyl, 2-oxetanylmethyl, 3-oxetanylmethyl, oxolanylmethyl, dioxolanylmethyl, formyl, acetyl, etc. These organic groups are preferably used.

  The N-substituted polyamideimide of the present invention can be synthesized by any method shown below. The first method is a method in which a diamino compound and a carboxylic acid are reacted to synthesize a polyamideimide, and then a hydrogen atom of an amide bond (CONH) of the obtained polyamideimide is substituted with a monovalent organic group (hereinafter referred to as “polyamideimide”). , Sometimes referred to as post-substitution method). That is, polyamideimide is dissolved in a solvent such as dimethyl sulfoxide, N-methylpyrrolidone, N, N-dimethylformamide or N, N-dimethylacetamide, and then sodium methoxide, sodium hydride, potassium hydride, sodium hydroxide, water After reacting with a base such as potassium oxide, butyllithium or triethylamine, an N-substituted polyamideimide can be obtained by reacting with a monovalent organic group halide.

Another method for synthesizing the N-substituted polyamideimide of the present invention is to use a diamino compound (N-substituted diamino compound) in which H of an amino group (NH ₂ ) is previously substituted with the monovalent organic group as a raw material. (Hereinafter sometimes referred to as pre-substitution method). This N-substituted diamino compound is (1) dehydrating and condensing a diamino compound with an aldehyde such as propyl aldehyde or benzaldehyde, or a ketone such as methyl ethyl ketone or cyclohexanone to reduce the double bond of this imine. Method: (2) A method in which a diamino compound is reacted with an acid halide such as acetyl chloride or benzoic acid chloride to form an amide compound, and the carbonyl group of the amide is reduced with lithium aluminum hydride or the like; and (3) N -Method for obtaining N, N'-substituted diaminodiphenylmethanes by reacting N-substituted anilines such as methylaniline, N, N-diphenylamine or N-methyl-3-aminotoluene with formaldehyde in the presence of an acid catalyst Refer to known organic synthesis methods such as Therefore, it can be easily obtained.

Next, a method for producing polyamideimide will be described. The reaction for forming an amide bond is carried out by converting a carboxylic acid halide and an amino group, if necessary, in the presence of a solvent such as dimethyl sulfoxide, N-methylpyrrolidone, N, N-dimethylformamide or N, N-dimethylacetamide. It can be carried out by reacting with pyridine or triethylamine in a temperature range of 0 to 300 ° C. Alternatively, a carboxyl group and an amino group may be converted to (PhO) ₃ P, (PhO) PCl ₂ , PhPOCl ₂ or (C ₃ H ₇ ) ₃ P (O) O as necessary in the presence of the above-described solvent. An amide bond can also be produced by reacting with pyridine in the range of 0 to 300 ° C. using a condensing agent such as. On the other hand, the formation of an imide bond is carried out by reacting a cyclic dicarboxylic acid anhydride structure with an amino group in the presence of the above-mentioned solvent in the range of 0 to 100 ° C. to obtain an amic acid structure, which is then combined with pyridine and acetic anhydride. And can be carried out by reacting in the range of 0 to 200 ° C.

  Moreover, even if it uses the diisocyanate compound obtained by making a diamino compound, a phosgene dimer, etc. react, the reaction which produces | generates an amide bond and the reaction which produces | generates an imide bond can be implemented. In this case, the reaction for forming an amide bond is carried out by reacting the carboxyl group and the isocyanate group in the diisocyanate compound in the presence of a solvent such as the above-mentioned solvent or diglyme, tetrahydrofuran, cyclohexanone, methyl ethyl ketone, acetonitrile, or γ-butyrolactone. If necessary, react with a catalyst such as tertiary amines, alkali metal compounds, alkaline earth metal compounds or a small amount of water, aromatic hydrocarbons such as xylene, toluene, etc. in the range of 0-300 ° C. Can do. If a cyclic dicarboxylic acid anhydride structure is used instead of the carboxyl group, an imide bond can be directly generated in the same manner as the reaction for generating an amide bond.

  Therefore, as a preferred method for synthesizing polyamideimide in the present invention, (i) at least one carboxylic acid having an acid anhydride structure and an acid halide group, (ii) having an acid anhydride structure and an acid halide group At least one carboxylic acid and at least one dicarboxylic diacid halide; (iii) at least one carboxylic acid having an acid anhydride structure and an acid halide group; and tetracarboxylic acids (tetracarboxylic dianhydride, tetra (Iv) dicarboxylic acid diacid halide, at least one of carboxylic acid tetraacid halide, or a derivative in which two carboxyl groups of tetracarboxylic acid have an anhydride structure and the remaining two carboxyl groups are acid halided) And at least one of the tetracarboxylic acids, or (v) a cyclic di A carboxylic acid raw material and a diamino compound of any combination of at least one carboxylic acid having a rubonic acid anhydride structure and an acid halide group, at least one dicarboxylic diacid halide, and at least one tetracarboxylic acid; First, the acid anhydride structure and amino group are reacted in the presence of a solvent, then pyridine or triethylamine or the like is added to react the acid halide group and amino group to synthesize polyamidoamic acid, and then acetic anhydride. And heating and heating the amidic acid structure.

  The following examples of methods for synthesizing polyamideimide include (vi) at least one carboxylic acid having an acid anhydride structure and a carboxyl group, and (vii) at least one carboxylic acid having an acid anhydride structure and a carboxyl group. At least one species and dicarboxylic acid, (viii) at least one carboxylic acid having an acid anhydride structure and a carboxyl group and at least one tetracarboxylic dianhydride, (ix) at least one dicarboxylic acid and At least one tetracarboxylic dianhydride, or (x) at least one carboxylic acid having an acid anhydride structure and a carboxyl group, at least one dicarboxylic acid and at least one tetracarboxylic dianhydride. Any combination of the carboxylic acid raw material and the diisocyanate compound is used as a solvent. In the presence, in a method of reacting in the range of 0 to 300 ° C. with a catalyst such as tertiary amines, alkali metal compounds, alkaline earth metal compounds or a small amount of water, aromatic hydrocarbons such as xylene and toluene as necessary. is there.

Further, any one of the combinations (vi) to (x) of the carboxylic acid raw material and a diamino compound are used, and in the presence of a solvent, an acid anhydride structure and an amino group are first reacted, and then (PhO) ₃ P, (PhO ) After synthesizing polyamidoamic acid by reacting with a condensing agent such as PCl ₂ , PhPOCl ₂ or (C ₃ H ₇ ) ₃ P (O) O and pyridine in the range of 0 to 300 ° C., acetic anhydride It is also possible to heat and heat the amidic acid structure to form a polyamidoimide.

（式中、Ｔ^１はトリカルボン酸類由来の有機残基であり、Ｄ^１はジアミノ化合物由来の有機残基であり、Ｒ^１は１価の有機基である。）In order to synthesize the N-substituted polyamideimide of the present invention by the pre-substitution method, the N-substituted diamino compound may be used as a raw material in place of the diamino compound in the polyamideimide synthesis method. In some cases, a carboxylic acid having an N-substituted amide bond represented by formula (24) is synthesized from a carboxylic acid having an acid anhydride structure and an acid halide group and the N-substituted diamino compound, and the diamino compound And a polyamic acid having an N-substituted amide bond, and then imidized. Alternatively, the compound of formula (24) and a diisocyanate compound may be reacted.

(In the formula, T ¹ is an organic residue derived from a tricarboxylic acid, D ¹ is an organic residue derived from a diamino compound, and R ¹ is a monovalent organic group.)

  However, compared with this pre-substitution method, the post-substitution method is superior in reactivity and gives an N-substituted polyamideimide having a high molecular weight. Therefore, when this is used as a liquid crystal alignment film, since the mechanical properties of the film itself are good, it is possible to avoid defects such as the film being scraped or disordered in the liquid crystal alignment in the rubbing step for imparting liquid crystal alignment.

  The molecular weight of the N-substituted polyamideimide of the present invention is, for example, preferably about 10,000 to 500,000, more preferably 20, in terms of polystyrene-reduced weight average molecular weight (Mw) of gel permeation chromatography (GPC). 000-200,000.

  The liquid crystal aligning agent varnish of the present invention is a composition containing the above-mentioned N-substituted polyamideimide and a solvent, and is used as a uniform solution. This liquid crystal aligning agent varnish contains N-substituted polyamideimide as an essential component, but other polymer compounds can be used in combination as long as the effects of the present invention are not impaired. Examples of the polymer compound that can be used in combination with the N-substituted polyamideimide of the present invention include materials such as polyamic acid, soluble polyimide, and polyamide that are generally used in liquid crystal aligning agent varnishes. By using these other polymer compounds together, it is possible to further improve the characteristics as a liquid crystal aligning agent.

  The concentration of the polymer compound in the liquid crystal aligning agent varnish of the present invention is preferably 0.1 to 40% by weight. When applying the liquid crystal aligning agent varnish to the substrate, it may be necessary to dilute the varnish with a solvent in advance to adjust the film thickness. In order to be able to dilute, it is necessary to keep the concentration of the polymer compound within a range not exceeding 40% by weight. In order to maintain a good film thickness in the spinner method or the printing method, the content is usually 10% by weight or less. In other coating methods such as dipping, the concentration may be lower than 10% by weight. On the other hand, when the concentration of the polymer compound is less than 0.1% by weight, the problem that the film thickness of the obtained liquid crystal alignment film becomes too thin tends to occur. Accordingly, the concentration of the polymer compound is suitably 0.1% by weight or more, preferably about 0.5 to 10% by weight in the usual spinner method or printing method. However, depending on the coating method of the varnish, it may be used at a dilute concentration.

  In the liquid crystal aligning agent varnish of the present invention, the solvent for dissolving the N-substituted polyamideimide is not particularly limited as long as it is a liquid having the ability to dissolve the polymer compound. Therefore, it may be appropriately selected according to the purpose of use from among solvents usually used in the production process and usage of polyamideimide, polyamic acid, soluble polyimide, polyamide and the like. Examples of these solvents include aprotic polar organic solvents which are the parent solvents for the above polymers, such as N-methyl-2-pyrrolidone, dimethylimidozolidinone, N-methylcaprolactam, N-methylpropionamide, N, N -Dimethylacetamide, dimethyl sulfoxide, N, N dimethylformamide, N, N-diethylformamide, diethylacetamide or γ-butyllactone can be used.

  In addition, for the purpose of improving applicability and the like, a mixed solvent obtained by adding another solvent to the above solvent can also be used. Other solvents used for such purposes include, for example, alkyl lactate, 3-methyl-3-methoxybutanol, tetralin, isophorone, ethylene glycol monoalkyl ethers such as ethylene glycol monobutyl ether, and diethylene glycol monoalkyls such as diethylene glycol monoethyl ether. Ether, ethylene glycol monoalkyl acetate, ethylene glycol monophenyl acetate, triethylene glycol monoalkyl ether, propylene glycol monoalkyl ether such as propylene glycol monobutyl ether, dipropylene glycol monoalkyl ether such as dipropylene glycol monomethyl ether, diethyl malonate Dialkyl malonates such as these, and the OH of these solvents are esterified Compounds and the like.

  The liquid crystal aligning agent varnish of the present invention can contain various additives as necessary. For example, if it is desired to improve the coating property, a surfactant according to such purpose, an antistatic agent if it is necessary to improve the antistatic property, and a silane cup if it is desired to improve the adhesion to the substrate. A ring agent or a titanium-based coupling agent may be blended. The liquid crystal aligning agent varnish obtained in this way is suitable mainly for the formation of a liquid crystal alignment film for TFT, but can provide an appropriate pretilt, so that it can provide an appropriate pretilt, and an STN type liquid crystal for ordinary TN type liquid crystal display elements. It is also useful when forming liquid crystal alignment films for display elements, IPS liquid crystal display elements, VA liquid crystal display elements, OCB liquid crystal display elements, ferroelectric liquid crystals, or antiferroelectric liquid crystal display elements. In addition, since it has excellent electrical characteristics as a liquid crystal display element, it can be used for a protective film, an insulating film, and the like.

  A liquid crystal alignment film faces a substrate on which a liquid crystal alignment film is formed using the liquid crystal alignment agent varnish of the present invention and another substrate on which a liquid crystal alignment film that may be the same as or different from the substrate is formed. Thus, a liquid crystal display substrate can be obtained by sandwiching liquid crystal therebetween, and a liquid crystal display element can be obtained by a known method. Formation of a liquid crystal aligning film is performed by the process of apply | coating a liquid crystal aligning agent varnish on a board | substrate, the subsequent drying process, and the heat processing process required for spin-drying | dehydration and ring closure reaction. As a coating method, a spinner method, a printing method, a dipping method, a dropping method, and the like are generally known, but these methods are also applicable in the present invention. In addition, as a method of the drying step and the step of performing the heat treatment necessary for the dehydration / ring closure reaction, a method of heat treatment in an oven or an infrared furnace, a method of heat treatment on a hot plate, etc. are generally known. These methods are also applicable in the present invention. The drying step is preferably performed at a relatively low temperature within a range where the solvent can be evaporated, and the heat treatment step is preferably performed at a temperature of about 150 to 300 ° C.

  Liquid crystal compositions that are preferably used in the liquid crystal display element of the present invention include, for example, those disclosed in JP-A-8-157828, JP-A-8-231960, JP-A-9-241644, and the like for STN type liquid crystal display elements. Examples of the liquid crystal composition disclosed in Kaihei 9-302346 include TFT type liquid crystal display elements (TN type, IPS type, VA type, OCB type). JP-A-8-199168, JP-A-9 -235552, JP-A-9-241463, JP-A-10-204016, JP-A-10-204436, JP-A-10-231482, and JP-A-2000-087040 The liquid crystal composition mainly composed of the compositions disclosed therein can be used preferably.In addition, one or more optically active compounds can be added to the liquid crystal composition.

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Further, in this example, an example in which N-substituted polyamideimide and polyamic acid are used in combination for the purpose of further improving the characteristics is given, but N-substituted polyamideimide is used as long as the effect of the present invention is not impaired. Even if used alone, there is no problem.
The abbreviations of the raw materials used in each Example and Comparative Example and the corresponding compound names are shown below.
TPA: terephthalic acid dichloride TMA: trimellitic anhydride chloride PMDA: pyromellitic dianhydride CBDA: cyclobutanetetracarboxylic dianhydride BDA: butanetetracarboxylic dianhydride DPM: 4,4'-diaminodiphenylmethane 4CB1B: 1,1-bis (4-((4-aminophenyl) methyl) phenyl) -4-butylcyclohexane 5CCBOB: 1,1-bis (4- (4-aminophenoxy) phenyl) -4- (4-pentylcyclohexyl) ) Cyclohexane 5CCB1P: 5- (4- (4- (4-pentylcyclohexyl) cyclohexyl) phenyl) methyl-1,3-diaminobenzene 6BOB: 2,2-bis (4- (4-aminophenoxy) phenyl) -hexane 5CCDPM: 1- (4-Pentyl Kurohekishiru) -4- (5-amino-benzyl-2-aminophenyl) cyclohexane NMP: N-methyl-2-pyrrolidone BC: butyl cellosolve

Example 1
(Synthesis of polyamideimide)
A 300 ml four-necked flask equipped with a thermometer, stirrer, condenser, raw material inlet, and nitrogen gas inlet is charged with 5.001 g of DPM, 6.828 g of 4CB1B , and 100.0 g of dehydrated NMP and dried. It melt | dissolved by stirring under nitrogen stream. The solution was cooled to 5 ° C., 8.171 g of TMA was added, and reacted at 25 ° C. for 4 hours. Thereafter, 15.34 g of pyridine was added, and the mixture was further reacted at 25 ° C. for 15 hours to synthesize a viscous polyamideamidic acid solution. To this, 64.66 g of dehydrated NMP and 27.74 g of acetic anhydride were sequentially added and reacted at 50 ° C. for 3 hours. The obtained reaction solution was put into a large amount of methanol, and the precipitated polymer was separated by filtration. After the obtained polymer was dissolved again in NMP, it was reprecipitated from pure water, filtered and dried under reduced pressure to obtain 16.5 g of polyamideimide. This polyamideimide is referred to as PAI-1.
PAI-2 to PAI-8 polyamideimides were synthesized by operating under the same conditions except that the types and compositions of carboxylic acids and diamino compounds were changed. Table 22 shows the raw material composition of the obtained polyamideimide.

Example 2
(Synthesis of N-substituted polyamideimide)
In a 100 ml four-necked flask equipped with a thermometer, a stirrer, a condenser, a raw material inlet, and a nitrogen gas inlet, the polyamideimide (PAI-1) 3.00 g obtained in Example 1 and dehydrated NMP 47.00 g were added. The mixture was stirred and dissolved at 25 ° C. for 1 hour. To this solution, 0.651 g of sodium hydride was added and reacted at 25 ° C. for 15 hours, and further reacted at 50 ° C. for 3 hours. To this reaction solution, 2.402 g of methyl iodide was added and reacted for another 15 hours. From the obtained final reaction solution, a polymer was obtained by the same reprecipitation operation as the above-mentioned polyamideimide (PAI-1), and this polymer was dried under reduced pressure to obtain 2.2 g of N-substituted polyamideimide. This N-substituted polyamideimide is designated as NPAI-1.
The N-substituted polyamideimide (NPAI-2 to NPAI-12) was converted by the same procedure as in NPAI-1, except that the type of raw material polyamideimide was changed or methyl iodide was changed to another halide. Synthesized. Table 23 shows the substituents and weight average molecular weight of the obtained N-substituted polyamideimide.
NPAI 9-12 in Table 23 are data of N-substituted polyamideimides synthesized using ethyl bromide, n-heptyl bromide, benzyl bromide, and anthrylmethyl bromide instead of methyl iodide, respectively. is there.

Synthesis example 1
(Synthesis of polyamic acid)
4.891 g of DPM and 90.0 g of dehydrated NMP were placed in a 500 ml four-necked flask equipped with a thermometer, stirrer, condenser, raw material inlet, and nitrogen gas inlet, and stirred under a dry nitrogen stream. And dissolved. While maintaining the temperature of the solution at 5 ° C., 2.690 g of PMDA and 2.419 g of CBDA were sequentially added and reacted at 25 ° C. for 30 hours. 100.0 g of BC was added to the reaction solution to obtain 200 g of a polyamic acid solution having a polymer concentration of 5.0%. This polyamic acid solution is designated as PA acid-1. The obtained polyamic acid had a weight average molecular weight of 75,000.

Synthesis example 2
(Polyamide synthesis)
A 500 ml four-necked flask equipped with a thermometer, stirrer, condenser, raw material inlet, and nitrogen gas inlet was charged with 3.216 g of TPA, 1.919 g of DPM, and 4.866 g of 4CB1B. 8.63 g of dehydrated NMP and 9.33 g of pyridine were added to make a homogeneous solution. To this solution, 12.01 g of triphenyl phosphite, 4 g of lithium chloride, and 12 g of calcium chloride were sequentially added, followed by reaction at 100 ° C. for 2 hours. From the obtained reaction solution, a polymer was obtained by the same reprecipitation operation as in the case of the polyamideimide (PAI-1) described above, and this was dried under reduced pressure to obtain 7.9 g of polyamide. This polyamide is designated as PA-1. The obtained polyamide had a weight average molecular weight of 88,000.

Synthesis example 3
(Synthesis of N-substituted polyamide)
In a 200 ml four-necked flask equipped with a thermometer, stirrer, condenser, raw material inlet, and nitrogen gas inlet, the polyamide (PA-1) 5.026 g and 26.39 g of dehydrated NMP obtained in Synthesis Example 2 were added. And dissolved by stirring at room temperature. To this solution, 0.934 g of sodium hydride was added and reacted for 40 minutes, and then 3.037 g of methyl iodide was added thereto and reacted for another hour. From the obtained reaction liquid, a polymer was obtained by the same reprecipitation operation as in the case of the polyamideimide (PAI-1) described above, and this was dried under reduced pressure to obtain 3.5 g of N-substituted polyamide. This N-substituted polyamide is designated as NPA-1. The obtained N-substituted polyamide had a weight average molecular weight of 52,000.

Synthesis example 4
(Synthesis of soluble polyimide)
A 300 ml four-necked flask equipped with a thermometer, stirrer, condenser, raw material inlet, and nitrogen gas inlet was charged with 5.125 g DPM, 6.997 g 4CB1B, and 100.0 g dehydrated NMP, and dried nitrogen. The mixture was dissolved by stirring under an air stream. The solution was cooled to 5 ° C., 7.879 g of BDA was added, and reacted at 25 ° C. for 15 hours to obtain a viscous polyamic acid solution. To this solution, 64.66 g of dehydrated NMP and 27.74 g of acetic anhydride were sequentially added, followed by reaction at 100 ° C. for 3 hours. From the obtained reaction solution, a polymer was obtained by the same reprecipitation operation as in the case of the aforementioned polyamideimide (PAI-1), and this was dried under reduced pressure to obtain 16.0 g of soluble polyimide. This soluble polyimide is designated as PI-1. In addition, the weight average molecular weight of the obtained polyimide was 49,000.

Examples 3-1 to 3-12 and Comparative Examples 1 to 3
(Preparation of liquid crystal alignment agent varnish)
0.10 g of each of the above-mentioned N-substituted polyamideimide NPAI-1 to 12, polyamide PA-1, N-substituted polyamide NPA-1 and soluble polyimide PI-1 was added to each 18 of PA acid-1 obtained in Synthesis Example 1. After individually adding to 0.0 g and dissolving, it is diluted with an NMP-BC mixed solvent (weight ratio 1/1), and the liquid crystal aligning agent having a polymer concentration of 3% by weight, corresponding to each type of N-substituted polyamideimide, etc. A varnish was obtained. The respective ratios of N-substituted polyamideimide NPAI-1 to 12, polyamide PA-1, N-substituted polyamide NPA-1 and soluble polyimide PI-1 to the polyamic acid in these liquid crystal alignment agent varnishes are all 1 by weight. / 9.

Example 4
(Preparation of alignment film evaluation cell)
(1) Production of cell for evaluating residual charge and voltage holding ratio (cell for measuring electrical characteristics) On a glass substrate with transparent electrode ITO, the NPAI-1-containing liquid crystal aligning agent varnish obtained in Example 3 was applied with a spinner. After pre-baking at 80 ° C. for about 5 minutes, heat treatment was performed at 250 ° C. for 30 minutes. The surface of the substrate on which the alignment film was formed was rubbed with a rubbing apparatus to perform an alignment treatment. Next, a gap material for 7 μm was sprayed on the alignment film surface of this substrate, and another substrate prepared in exactly the same manner was overlaid with the surface on which the alignment film was formed facing inward. Then, the periphery of the two superimposed substrates was sealed with an epoxy curing agent leaving a liquid crystal injection hole, and an anti-parallel cell with a gap of 7 μm was produced. The following liquid crystal composition was injected into this cell, a photo-curing agent was applied to the liquid crystal injection hole, cured by UV irradiation, and the injection port was sealed. Next, a heat treatment was performed at 110 ° C. for 30 minutes to obtain a cell for evaluating residual charge and voltage holding ratio. For other liquid crystal aligning agent varnishes, cells for evaluating residual charge and voltage holding ratio were prepared in the same manner.
The composition of the liquid crystal composition used is shown below. The NI point of this composition was 100.0 ° C., and the refractive index anisotropy value was 0.093.

(2) Preparation of pretilt angle measurement cell Anti-parallel having a cell thickness of 20 μm in the same manner as in the preparation of the electrical property measurement cell, except that a 20 μg gap material was used instead of the 7 μg gap material. A cell was manufactured and used as a pretilt angle measurement cell. In addition, the liquid crystal composition used when manufacturing this cell is the same liquid crystal composition as that used when manufacturing the cell for measuring electrical characteristics.

Example 5
(Evaluation of liquid crystal alignment agent varnish)
(1) Evaluation method i) Measurement of residual charge Hysteresis voltage was measured by the method described in "Miyake et al., Shingaku Technical Report EID91-111, p19". Note that an AC voltage of 50 mV and 1 kHZ was applied to the liquid crystal cell, and a direct current triangular wave with a frequency of 0.0036 HZ was superimposed on the liquid crystal cell.
ii) Measurement of voltage holding ratio The voltage holding ratio was measured by the method described in "Mizushima et al., Proceedings of the 14th Liquid Crystal Symposium p78". The measurement conditions are a gate width of 69 μs, a frequency of 60 Hz, a wave height of ± 4.5 V, and a measurement temperature of 60 ° C.
iii) Measurement of pretilt angle The pretilt angle of the liquid crystal was measured by the crystal rotation method.
iv) Evaluation of liquid crystal alignment The liquid crystal alignment was determined by observing the cell when measuring the pretilt angle under a polarizing microscope and determining the presence or absence of a domain.
v) Evaluation of coating property A liquid crystal alignment agent varnish was applied with a spinner, pre-baked at 80 ° C for about 5 minutes, and then heat-treated at 250 ° C for 30 minutes, and the alignment film surface was visually observed, Judgment was made based on the presence or absence of pinholes and uneven coating.

(2) Evaluation result About the liquid crystal cell for evaluation corresponding to each of the liquid crystal aligning agent varnish of Examples 3-1 to 3-12 and Comparative Examples 1-3 obtained in Example 4, the method of said (1) The results are shown in Table 24.

  The lower the residual charge value, the better. The higher the voltage holding ratio, the better. From the above results, the liquid crystal aligning agent varnish using the N-substituted polyamideimide of the present invention has a residual charge and voltage holding ratio as compared with the liquid crystal aligning agent varnish using the polyamide, N-substituted polyamide and soluble polyimide of the comparative example. It can be seen that the electrical properties such as the pretilt angle, the orientation properties such as the liquid crystal orientation, and the coating properties are excellent in overall balance.

Effect of the invention

  By using the N-substituted polyamideimide of the present invention, it is possible to obtain a liquid crystal display device that has good liquid crystal alignment and coating properties, can adjust the pretilt angle arbitrarily, has no image sticking, and has excellent voltage holding ratio and residual charge. . The liquid crystal aligning agent varnish of the present invention is particularly preferably used in a TFT type liquid crystal display element (TN type, IPS type, VA type, OCB type), but it has excellent electrical characteristics and the pretilt angle can be arbitrarily adjusted. It can also be used as an aligning agent for type liquid crystal display elements, ferroelectric liquid crystals, and antiferroelectric liquid crystal display elements. Moreover, since the thin film by this liquid crystal aligning agent varnish is excellent in an electrical property, you may use it as a protective film or an insulating film.

Claims (5)

It has only the structural unit represented by Formula (1-1) among the structural units represented by the following formula (1-1), formula (1-2), and formula (1-3), respectively. Or a polyamideimide having two or more of these three structural units, wherein at least one of organic residues T ² derived from carboxylic acids and organic residues D ^{1 to} D ³ derived from diamino compounds is A polyamideimide, which is an organic residue having a side chain group having 3 or more carbon atoms, wherein 30 mol% or more of all amide bonds in the polymer are amide bonds in which a monovalent organic group is bonded to N.
[Chemical 1]

(Wherein T ^{1 to} T ³ are organic residues derived from carboxylic acids, D ^{1 to} D ³ are organic residues derived from a diamino compound, and R ^{1 to} R ³ are each independently hydrogen or monovalent. This monovalent organic group is a linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched hydroxyalkyl group having 1 to 8 carbon atoms, or a linear or branched group having 2 to 20 carbon atoms. Alkoxyalkyl, an unsaturated aliphatic group having 2 to 15 carbon atoms, a group having an alicyclic group, an aromatic hydrocarbon group, a group containing an O-containing heterocyclic system, a group having a steroid skeleton, a group having a carbonyl group , An organosilyl group, and one or more groups selected from the group consisting of an organosilyl group-containing group, and any H in the alkyl may be substituted with F, and the aromatic carbon In hydrogen groups, aromatic rings and al Or H may be substituted with F, and one H of the aromatic ring may be substituted with CN. Here, the organic residue T ¹ derived from tricarboxylic acids is selected from the group of groups represented by the following formulas (9 ′) to (16 ′), and has a side chain having 3 or more carbon atoms in T ² . The organic residue derived from dicarboxylic acids is selected from the group of groups represented by the following formulas (7 ′) and (8 ′), and the organic residue T ³ derived from tetracarboxylic acids is 1, 2, 3, 4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,5,6-cyclohexanetetracarboxylic dianhydride, bicyclo (2,2,2 ) -Oct (7) -ene-2,3,5,6-tetracarboxylic acid di Water, 3,3′-bicyclohexyl-1,1 ′, 2,2′-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 5- (2,5-di Oxotetrahydrofural) -3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5-tetrahydro-2,5-dioxo-3-furanyl ) -Naphtho [1,2, -c] -furan-1,3-dione, 3,5,6-tricarboxynorbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic acid Anhydride, ethylenetetracarboxylic dianhydride, butanetetracarboxylic dianhydride, pentanetetracarboxylic dianhydride, hexanetetracarboxylic dianhydride, heptanetetracarboxylic dianhydride, Lomellitic dianhydride, 3,3 ′, 4,4′-diphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2,3,6,7- Naphthalene dianhydride, 3,3′-4,4′-biphenylsulfone tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyl ether tetracarboxylic dianhydride, 3,3 ′ , 4,4′-dimethyldiphenylsilanetetracarboxylic dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 4,4′-bis (3,4-dicarboxy) Phenoxy) diphenylsulfone dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ′, 4,4′-perfluoropyridene diphthalic dianhydride, 3,3 ', 4,4'-Biff Nyltetracarboxylic dianhydride, bis (phthalic acid) phenylsulfin oxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, An acid anhydride group of a compound selected from bis (triphenylphthalic acid) -4,4′-diphenyl ether dianhydride and bis (triphenylphthalic acid) -4,4′-diphenylmethane dianhydride; The organic residue derived from a diamino compound having a side chain of 3 or more carbon atoms, which is defined by deletion, is selected from the group of groups represented by each of the following formulas (2) to (5). )
[Chemical 2]

[Chemical Formula 3]

(Wherein X ⁶ is a single bond, O, COO, OCO, NH, NHCO, CONH, S, or alkylene having 1 to 6 carbon atoms, and R ¹¹ is an alkyl or fluoroalkyl group having 3 to 20 carbon atoms, or It is a steroid group which may have a substituent.)
[Formula 4]

(In the formula, R ¹² and R ¹³ are each independently alkyl having 1 to 12 carbon atoms, but the total number of carbon atoms is 4 or more.)
[Chemical formula 5]

(Wherein R ⁴ is H or alkyl having 1 to 12 carbon atoms, ring A is 1,4-phenylene or 1,4-cyclohexylene, and Z ¹ and Z ² are each independently a single bond. CH ₂ , CH ₂ CH ₂ or O, r is 0 to 3, s is 0 to 5, t1 is 0 to 3, and t2 is an integer of 0 to 3, but t1 is 2 to 3. A plurality of Z ¹ at the time may be the same or different from each other, and a plurality of Z ² when t 2 is 2 to 3 may be the same or different from each other. , 4-phenylene or 1,4-cyclohexylene may optionally be substituted with alkyl having 1 to 4 carbon atoms.)
[Chemical 6]

(Wherein, X ¹ and X ² are each independently a single bond, O, COO, OCO, NH, CONH or alkylene having 1 to 12 carbon atoms, and G ¹ and G ² are each independently a single bond, Or a divalent group containing 1 to 3 rings selected from an aromatic ring and an alicyclic ring, and R ⁵ is H, F, CN, OH or an alkyl, fluoroalkyl or alkoxy having 1 to 12 carbon atoms And the position of the substituent on the benzene ring and the position of the two free radicals are arbitrary, provided that when G ² is a single bond and X ² is neither a single bond nor alkylene, R ⁵ Is H or alkyl, and when G ¹ and G ² are both a single bond, the total carbon number of X ¹ , X ² and R ⁵ is 3 or more.)
[Chemical 7]

(Wherein X ³ and X ⁴ are each independently a single bond, CH ₂ , CH ₂ CH ₂ or O, and R ⁶ and R ⁷ are each independently H, alkyl having 1 to 12 carbons, or A perfluoroalkyl having 1 to 12 carbon atoms, wherein at least one of R ⁶ and R ⁷ is an alkyl or perfluoroalkyl having 3 or more carbon atoms, and u1 and u2 are each independently an integer of 0 to 3 However, the plurality of X ³ when u1 is 2 to ³ may be the same or different from each other, and the plurality of X ⁴ when u2 is 2 to 3 are also the same as each other. And any H in 1,4-phenylene may be substituted with alkyl having 1 to 4 carbon atoms.)
[Chemical 8]

(In the formula, R ⁸ is H, or linear or branched alkyl having 1 to 12 carbon atoms, and one or a plurality of non-adjacent CH ₂ in the alkyl may be substituted with O; X ⁵ is a single bond or alkylene having 1 to 5 carbon atoms, and one or a plurality of non-adjacent CH ₂ in the alkylene may be substituted with O, and m is an integer of 0 to 3. , N is an integer of 1 to 5. The bonding position of the substituent and the free radical to the benzene ring is an arbitrary position. R ¹ , R ² and R ³ are each independently H or a monovalent organic group having 5 or less carbon atoms, and 50 mol% or more of the total amount of R ^{1 to} R ^{3 is} the monovalent organic group. The polyamide-imide according to claim 1, wherein
R ¹ , R ² and R ³ are each independently H, alkyl having 5 or less carbon atoms or oxygen-containing alkyl having 5 or less carbon atoms, and 70 mol% or more of the total amount of R ^{1 to} R ³ is the alkyl The polyamideimide according to claim 1, which is a monovalent organic group selected from oxygen-containing alkyl and oxygen-containing alkyl.
A liquid crystal aligning agent varnish comprising the polyamideimide according to any one of claims 1 to 3 .
A liquid crystal display element, wherein the liquid crystal aligning agent varnish according to claim 4 is used.